Abstract
Objective
Human cervical cancer is caused by the high-risk types of human papillomavirus (HPV) such as HPV16, which possess the E6 and E7 oncogenes, whose expressions are a prerequisite for cancer development. We performed this study to compare the efficacy of antitumor activity by HPV siRNA which silences only E6 or both E6/E7.
Methods
We transfected siRNA 377 (HPV16 E6 siRNA), siRNA 3 (HPV16 E6 siRNA), and siRNA 198 (HPV16 E7 siRNA) into SiHa cell line (siRNA 377 silences only E6, and siRNA 3 and siRNA 198 silence both E6 and E7). We experimented cell counts and morphologic changes 24 and 48 hours after transfection and expressions of HPV16 E6/E7 mRNA by RT-PCR.
Figures and Tables
Fig. 1
Effects of siRNA on growth inhibition in SiHa cervical cancer cell line in vitro. Cells were transfected with universal siRNA, siRNA 3, siRNA 198 and siRNA 377 at 50 nM. Cells were trypsinized for direct cell counting after 24 and 48 hours. Cell growth inhibitions were compared with the universal siRNA control by t-test. *P<0.05, **P<0.01.
![kjog-53-35-g001](/upload/SynapseData/ArticleImage/0021kjog/kjog-53-35-g001.jpg)
Fig. 2
siRNA-mediated morphological and numerical changes in SiHa cervical cancer cell line in vitro. Cells were transfected with universal siRNA, siRNA 3, siRNA 198 and siRNA 377 at 50 nM. Typical photographs were shown after 48 hours (×400 for all photographs).
![kjog-53-35-g002](/upload/SynapseData/ArticleImage/0021kjog/kjog-53-35-g002.jpg)
Fig. 3
RT-PCR analysis for expressions of the HPV16 E6, E7 and β-actin mRNA. Cells were transfected with universal siRNA, siRNA 377, siRNA 3 and siRNA 198 at 50 and 100 nM. RNA was extracted for RT-PCR after 48 hours.
![kjog-53-35-g003](/upload/SynapseData/ArticleImage/0021kjog/kjog-53-35-g003.jpg)
Fig. 4
Effects of siRNA on p53 expressions in SiHa cell line. Cells were transfected with universal siRNA, siRNA 377, siRNA 3 and siRNA 198 at 50 nM. Immunoblot analysis using specific p53 antibody was performed after 24 and 48 hours. The cells were collected and the extracts (40 µg) were run on 10% SDS-PAGE.
![kjog-53-35-g004](/upload/SynapseData/ArticleImage/0021kjog/kjog-53-35-g004.jpg)
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